B-Vitamins, blood pressure and endothelial compliance in healthy adults stratified by MTHFR genotype

Hypertension affects 1 billion people worldwide and is a primary public health concern as the leading cause of premature mortality. A common polymorphism, the C677 T mutation in the gene, MTHFR, encoding the enzyme methylenetetrahydrofolate reductase (MTHFR) affects 12% of the UK and Irish population and is associated with an increased risk of hypertension(Reference McNulty, Strain and Hughes1). The activity of MTHFR, which generates the predominant co-factor form of folate, 5 methyl-tetrahydrofolate, is dependent on flavin adenine dinucleotide (FAD), the co-enzyme form of riboflavin. Individuals homozygous for the MTHFR 677TT genotype have reduced MTHFR enzyme activity resulting in lower 5 methyl-THF concentrations(Reference Antoniades, Shirodaria and Leeson2), however previous randomised controlled trials at our Centre have shown that blood pressure (BP) is highly responsive to riboflavin supplementation specifically in individuals with the TT genotype(Reference Horigan, McNulty and Ward3). The mechanism explaining how this gene-nutrient interaction influences BP is unknown, but it may involve a nitric oxide (NO)-mediated effect on endothelial function(Reference McNulty, Strain and Hughes1). The aim of this study was to investigate BP and endothelial function in adults stratified by MTHFR genotype.